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Evil! Like Black Play Doh
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Discussion Starter #1
Hoping someone can help with this.

We have just bought our first club boat, & while everything else is fairly straight forward ( relativly speaking )I am not sure how to make up a shot line.

More to the point how much weight is sufficient. Being Pikey, we have spliced 2 ropes so far, 25m & 35m, & are planning to use a 25L drum as a marker bouy.

This should give 25kgs of lift, but what should the shot weight be?

Have gone back through my old BSAC manuals, whilst they layout the basic config, none mention weight. Must have chucked loads over the side in other people's boats, but never really taken that much notice.

Any help, gratefully received.

Steve
 

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East coast, think I dive there !
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1,993 Posts
25 and 35m are very short, what depths are you diving?

There are several ways to do it, we use either shot weight or grapnel anchor.

Shot weight is literally that, a large lump that you can throw over, looking at about 15kg+ depending on the size of the boat. You can make one out of old roofing lead by welting it into an old bucket with a loop of wire in the top to tie the shot line to, or use anything with substantial weight such as old cast drainage piping.

Second method we use is an folding anchor, this is then used to drift over the wreck and bite in, that way you know your on the wreck. Once you get down you fold up the anchor and tie in a waster, once your dive is done you just reverse the boat and pull out the waster if all goes to plan. Your looking at about a 5-7kg anchor, again depending on boat size.

I prefer the second method, which ever you chose don't forget to put a length of chain between the shot/anchor and the shot line, this will help protect the rope on the wreck from been cut and also help keep the line down when your on slack and help prevent it shifting to an extent.
 

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"Three sheds"
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We use a 5kg folding grapnel. It's far better then a weight for wreck diving as it hooks in. Last pair in fold it up and then either send it up or attach a partially filled lifting bag to it to assist recovery (we tend to come up on a DSMB).

TBH I would get some decent rope - around 14mm thickness is about right. Get nice sailing rope and it's kinder on your hads. Also try and get a decent buoy. It's only going to cost you 20 quid or so for the rope, and the same for the buoy. If there's a climbing club near you you can get perfectly good rope that's taken too many falls from them for nowt. I got a small buoy for a fiver from a fisherman who found one drifting. Ebay is your friend if you're patient you can get a bargain. The buoy should have at least 50% bigger than the weight of the weight you are using (remember to include the chain)

You need to have more rope than the depth - about 25% is plenty otherwise you end up finning for ages on a horizontal shotline. We have several lengths of line which are marked up and can be shackled together depending on what we are diving.

Oh, and if you do go for a shotline then it should be around 20kg or so.

Janos

PS - I think this is in the Instructor manual, DT12 IIRC.
 

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The man who makes nice "SHINY" things
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1,706 Posts
They way i have my shots set up is between the shot line and the anchor or shot i have about 1m of heavy anchor chain then again 1-2m of rope this acts as a waister then the anchor/shot shackled to the end of the waister the idea is this is when you untie the shot and send it up you tie the waster rope on to the wreck, when you have finished your dive as we come back to our shots by reeling off the LAST PAIR back to the shot and if NO other lines are attached to the shot unties the shot from the wreck and you climb up the shot and drift with the current the idea of the piece of chain KEEPS the rope straight and STOPS it from floating up to the service.

At the other end of the shot line i have a small P buoy this tells me when it starts to get slack, the i have a large buoy then about 3-4 meters of rope then another buoy the idea of this one is if you MISS the main buoy you can then grab hold of this rope and pull yourself along to the main buoy then down the shot.

The first PAIR in sends up the shot buy a lift bag with a large crack bottle attached to the bag, this is an indication that the shot is tied in the wreck so the other divers can go in.

I have several lengths made up from 35-40m to 55m for the deeper wrecks.

I have also put a large ring through the shot line so it can run freely that is clipped at the top by the P buoy the idea of this if for any reason i have missed the wreck or i am using this as a down line for drift diving or looking for new wrecks i have a position point, i can connect a large buy to the ring connect the shot to something strong on the boat drive the boat away from the shot pulling the shot line and the ring & buoy runs down the shot line pulling the shot up then the Anchor hooks on to the ring then you just pull the shot in to the boat reset the ring at the top and then start again this save some poor person hauling up that heavy shot.

I got this idea from the fisherman in our local club who uses it all the time.

I will post some pictures of this some time over Easter.
 

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Evil! Like Black Play Doh
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348 Posts
Discussion Starter #5
Thanks

Cheers Guys, this is really helpful.

The rope has been cut to these lengths as the diving we intend to do first off will be within sight of land, as our own boat is a new thing for us. We aiming for a few of the wrecks out of Lyme Bay, that we have dived off a charter, that we know are in about 20 - 30m.

This serves two purposes, as we are familiar with the wrecks & the area, plus it's a nice start for the others in the club without much wreck - limited depth experience.

Will let you know how we get on, after sunday, which is our first outing. Thanks for the info, especially the recovery. It's a great help

Steve
 

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You could always have a grapple welded up out of mild steel bar. Then it can be simply tugged straight to release.
 

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Utrinque Paratus
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what ever shot you use if you have a counter weight the shot will always be above the wreck

Graham
 

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Evil! Like Black Play Doh
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348 Posts
Discussion Starter #8
Counter weight eh?

Graham,

Thanks for the reply, but maybe my brain isn't full in gear this morning, could you expand on this?

Do you mean to attach a small weight to the bottom of the main Bouy on a short lenght of rope?

Again, if any one can post a pic of a home made anchor/ Grapple that would be ace ( notice a theme here, 25L drum, home made grapple etc ). We are a little pikey, but as I mentioned, this is our first foray into our own boat, so I am anticipating having to leave or cut free an early attempt at the shot.

So I won't feel so bad about making anything & losing it, but when we start talking about actually buying & losing it...... well.....

Thanks again

Steve
 

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I think what Graham is alluding to is a lazy shot. You have 25kg at the bottom and a rope that comes up to the buoy. It passes through a clip on the buoy and then the end of the rope has a 5kg weight on it.
This way as the tide comes in or goes out the 5kg weight rises and falls.

The drawback is that the short end of the rope can get wrapped around the long end and thus become a fixed shot, or in strong tides the 5kg weight will be pulled up to the buoy giving you an angled shot.
 

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Evil! Like Black Play Doh
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348 Posts
Discussion Starter #10 (Edited)
Lazy shot

Thanks Neil, yep, you're right. After searching every where for some decent info on making a shot up ( BSAc manuals, trawling the net etc ) I remebered I had a copy of Lizzie Bird's "Wreck Diving Manual" in the attic.

Just climbed up there, dusted it off & spent the last few hours redaing up on shot's. It's quite informative.

But thanks again to everyone who has replied, & if anyone has any photo's that would be a great help, pics speaking a thousand words n' all that.

Steve
 

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Кевин ХuΦ
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674 Posts
Hi

If you have to larger bouy on the shot this will only act to move the weight in any tide or swell, I find that small hard floats are good and when its slack, they show and a larger bouy can be added with a clip
 

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Charter Boat Skipper, Salvage Diver & YBOD abuser
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1,605 Posts
Mild steel Grapnel (20lb is ample usually). Max depth of water around wreck of 8mm (ample) rope to 9" diameter hard plastic pot-buoy, 4m extra to 5-gall jar (square ones are best as they don't spin in the tide and wind things together) another 4-5m tail with a loop on end to make it easy to pick up.
Hoof it uptide of wreck (allowing for any windage effects on the boat) drag it into wreck. When 5 gall jar starts to flop it should be diveable by experienced divers, when pot buoy shows it should be diveable by anyone.
There are lots of release/ recovery/ tying-in methods, find one that suits your group/boat.

ATB,
Terry
 

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shot weight

the brass shellcase filled with lead looks good but you have to incude a u bolt to clip line to

howitzer shells work very well
malcolm w
 

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I think what Graham is alluding to is a lazy shot. You have 25kg at the bottom and a rope that comes up to the buoy. It passes through a clip on the buoy and then the end of the rope has a 5kg weight on it.
This way as the tide comes in or goes out the 5kg weight rises and falls.

The drawback is that the short end of the rope can get wrapped around the long end and thus become a fixed shot, or in strong tides the 5kg weight will be pulled up to the buoy giving you an angled shot.
What you've described is not a lazy shot but a top-tensioned shot.

A lazy shot is a deco line attached to the main shot at a point below the lowest stop level. It will normally involve a 'clocking in' system and the last diver up will disconnect the line allowing it to drift with the current.
 
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